In CRM Online 2013, I need to determine the start and end dates of daylight savings time based on a specific time zone. I have code that needs to display times converted for different time zones, aside from the time zone in the current user's settings. For example, if the current user's time zone is set to EST - Eastern Standard Time they will see date/time values in their local time, but I need to have a web resource on an entity form display that date/time converted to other time zones. I can get the standard offset for each time zone but can't find any accurate data that indicates the start month/day of daylight savings time so I know when to use that offset. Using the OData service endpoint I looked at TimeZoneDefinition and TimeZoneRule entities, and also at the user's current timezone in UserSettings entity. I checked the attributes on those entities but they have incorrect values for Daylight Savings month/day. For example, looking at EST time zone I see Daylight month and day of March 2nd, but it should be March 8.